Social inequalities in early childhood language development during the COVID-19 pandemic: a descriptive study with...

Social health inequalities are still of great public health importance in modern societies. The COVID-19 pandemic may have affected social inequalities in people's health due to containment measures. As these measures particularly affected children, they might have been particularly vulnerable to increased social inequalities. The aim of the study was to describe health inequalities during the pandemic based on language delay (LD) in children in order to inform public health interventions for a population at risk of long-term health and education inequalities.

Data of 5-7 year old children from three consecutive school entry surveys in the German federal state of Brandenburg were used, including data compulsorily collected before the pandemic (2018/2019: n = 19,299), at the beginning of the pandemic (2019/2020: n = 19,916) and during the pandemic (2020/2021: n = 19,698). Bivariate and multivariate binary regression analyses [OR, 95% CI] cross-sectionally examined the relationship between the prevalence of LD [yes/no] and social inequalities, operationalized by family socioeconomic position [SEP low/middle/high], migration background [native-German language/non-native German language] and length of kindergarten attendance [< 4 years/ ≥ 4 years]. Factors contributing to inequality in LD were examined by socioeconomic stratification.

Cross-sectionally, LD prevalence has decreased overall (2018/2019: 21.1%, 2019/2020: 19.2%, 2020/2021: 18.8%), and among children from both high SEP and native German-speaking families. As LD prevalence increased among children from families with low SEP and remained stable among non-native German speakers, social inequalities in LD prevalence increased slightly during the pandemic i) by low SEP (2018/2019: OR = 4.41, 3.93-4.94; 2020/2021: OR = 5.12, 4.54-5.77) and ii) by non-German native language (2018/2019: OR = 2.22, 1.86-2.66; 2020/2021: OR = 2.54, 2.19-2.95). During the pandemic, both migration background and kindergarten attendance determined LD prevalence in the high and middle SEP strata. However, the measured factors did not contribute to LD prevalence in children from families with low SEP.

Social inequalities in LD increased due to opposing trends in prevalence comparing low and high SEP families. To promote health equity across the life course, early childhood should be of interest for tailored public health actions (e.g. through targeted interventions for kindergarten groups). Further analytical studies should investigate determinants (e.g., parental investment).